Due to missing values for some individuals, numbers do not always add up to 366 female
and 149 male patients with RA and 478 female and 291 male controls. aAdjusted for birth year, year or pseudo-year of RA diagnosis, and (when combined)
gender. bOne pack-year is equivalent to 7,300 cigarettes (20 cigarettes per day for 1 year).
cTen years prior to interview. dOne drink is equivalent to one bottle of normal beer, 0.67 bottle of strong beer,
or one glass of wine, dessert wine, or spirits. eTrend tests on the original categories, which were enumerated by consecutive numbers
starting with one. fIncluding only individuals who had a job. CI, confidence interval; OR, odds ratio;
ref, reference.